Lecture_7a-Ross

Lecture_7a-Ross - Digital Modulation-1 Basic concepts on...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Elec 300u Digital Modulation (Part I), Slide 1 Digital Modulation-1 Basic concepts on digital communications Eye diagrams to examine waveforms Some content taken with permission from material developed for the course EECS6.02 by C. Sodini, M. Perrot and H. Balakrishnan
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Summary of Analog I/Q Modulation Frequency domain view Time domain view
Background image of page 2
M-ary data transmission Digital modulation operates by sending discrete valued symbols (e.g. +A, -A) through an analog communication channel - the communication system is referred to as binary if only two possible values are transmitted (i.e. 1-bit) the system is referred to as M-ary if M > 2 possible values are transmitted (e.g. M = 4 in 2- bit) time 3 1 -1 -3 time +A -A binary M-ary
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Advantages of going digital Allows communication systems to be constructed from “computers” Intricate processing possible Inexpensive to build (very cheap VLSI designs) Compare to analog where special circuits are needed Allows information to be “packetized” Efficiently send information as packets through network Analog modulation requires “circuit-switched” connections Allows error correction to be achieved Less sensitivity to channel imperfections Enables compression of information More efficient use of channel Supports a wide variety of information content Voice, text and email messages, video can all be represented as digital bit streams
Background image of page 4
Time 0111111
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 20

Lecture_7a-Ross - Digital Modulation-1 Basic concepts on...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online